Documents disponibles écrits par cet auteur

Effect of rib spacing on heat transfer in a two pass rectangular channel (AR = 2:1) at high rotation numbers / Lei Jiang in Journal of heat transfer, Vol 134 N° 9 (Septembre 2012) 

Public ISBD [article]  in Journal of heat transfer > Vol 134 N° 9 (Septembre 2012) . - 09 p. Titre : Effect of rib spacing on heat transfer in a two pass rectangular channel (AR = 2:1) at high rotation numbers Type de document : texte imprimé Auteurs : Lei Jiang, Auteur ; Je-Chin Han, Auteur ; Michael Huh, Auteur Année de publication : 2012 Article en page(s) : 09 p. Note générale : heat transfer Langues : Anglais (eng) Mots-clés : gas  turbine  heat  transfer;  forced  convection;  heat  transfer  enhancement Index. décimale : 536 Chaleur. Thermodynamique Résumé : In this paper, the effect of rib spacing on heat transfer in a rotating two-passage channel (aspect ratio, AR = 2:1) at orientation angle of 135 deg was studied. Parallel ribs were applied' on leading and trailing walls of the rotating channel at the flow angle of 45 deg. The rib-height-to-hydraulic diameter ratio (e/Dh) was 0.098. The rib-pitch-to-rib-height (P/e) ratios studied were 5, 7.5, and 10. For each rib spacing, tests were taken at five Reynolds numbers from 10,000 to 40,000, and for each Reynolds number, experiments were conducted at four rotational speeds up to 400 rpm. Results show that the heat transfer enhancement increases with decreasing P/e from 10 to 5 under nonrotation conditions. However, the effect of rotation on the heat transfer enhancement remains about the same for varying P/e from 10 to 5. Correlations of Nusselt number ratio (Nu/Nus) to rotation number (Ro) or local buoyancy parameter (Box) are existent on all surfaces (leading, trailing, inner and outer walls, and tip cap region) in the two-passage 2:1 aspect ratio channel. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO000134000009 [...] [article] Effect of rib spacing on heat transfer in a two pass rectangular channel (AR = 2:1) at high rotation numbers [texte imprimé] / Lei Jiang, Auteur ; Je-Chin Han, Auteur ; Michael Huh, Auteur . - 2012 . - 09 p. heat transfer Langues : Anglais (eng) in Journal of heat transfer > Vol 134 N° 9 (Septembre 2012) . - 09 p. Mots-clés : gas  turbine  heat  transfer;  forced  convection;  heat  transfer  enhancement Index. décimale : 536 Chaleur. Thermodynamique Résumé : In this paper, the effect of rib spacing on heat transfer in a rotating two-passage channel (aspect ratio, AR = 2:1) at orientation angle of 135 deg was studied. Parallel ribs were applied' on leading and trailing walls of the rotating channel at the flow angle of 45 deg. The rib-height-to-hydraulic diameter ratio (e/Dh) was 0.098. The rib-pitch-to-rib-height (P/e) ratios studied were 5, 7.5, and 10. For each rib spacing, tests were taken at five Reynolds numbers from 10,000 to 40,000, and for each Reynolds number, experiments were conducted at four rotational speeds up to 400 rpm. Results show that the heat transfer enhancement increases with decreasing P/e from 10 to 5 under nonrotation conditions. However, the effect of rotation on the heat transfer enhancement remains about the same for varying P/e from 10 to 5. Correlations of Nusselt number ratio (Nu/Nus) to rotation number (Ro) or local buoyancy parameter (Box) are existent on all surfaces (leading, trailing, inner and outer walls, and tip cap region) in the two-passage 2:1 aspect ratio channel. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JHTRAO000134000009 [...]

High rotation number effect on heat transfer in a triangular channel with 45 deg, inverted 45 deg, and 90 deg ribs / Yao-Hsien Liu in Journal of heat transfer, Vol. 132 N° 7 (Juillet 2010) 

Public ISBD [article]  in Journal of heat transfer > Vol. 132 N° 7 (Juillet 2010) . - pp. [071702-1/10] Titre : High rotation number effect on heat transfer in a triangular channel with 45 deg, inverted 45 deg, and 90 deg ribs Type de document : texte imprimé Auteurs : Yao-Hsien Liu, Auteur ; Michael Huh, Auteur ; Je-Chin Han, Auteur Article en page(s) : pp. [071702-1/10] Note générale : Physique Langues : Anglais (eng) Mots-clés : Heat  transfer  Turbulence  promoter  Triangular  channel  High  rotation  number Index. décimale : 536 Chaleur. Thermodynamique Résumé : Heat transfer and pressure drop have been experimentally investigated in an equilateral triangular channel (Dh=1.83 cm), which can be used to simulate the internal cooling passage near the leading edge of a gas turbine blade. Three different rib configurations (45 deg, inverted 45 deg, and 90 deg) were tested at four different Reynolds numbers (10,000–40,000), each with five different rotational speeds (0–400 rpm). The rib pitch-to-height (P/e) ratio is 8 and the height-to-hydraulic diameter (e/Dh) ratio is 0.087 for every rib configuration. The rotation number and buoyancy parameter achieved in this study were 0–0.58 and 0–2.3, respectively. Both the rotation number and buoyancy parameter have been correlated with predict the rotational heat transfer in the ribbed equilateral triangular channel. For the stationary condition, staggered 45 deg angled ribs show the highest heat transfer enhancement. However, staggered 45 deg angled ribs and 90 deg ribs have the higher comparable heat transfer enhancement at rotating condition near the blade leading edge region. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...] [article] High rotation number effect on heat transfer in a triangular channel with 45 deg, inverted 45 deg, and 90 deg ribs [texte imprimé] / Yao-Hsien Liu, Auteur ; Michael Huh, Auteur ; Je-Chin Han, Auteur . - pp. [071702-1/10]. Physique Langues : Anglais (eng) in Journal of heat transfer > Vol. 132 N° 7 (Juillet 2010) . - pp. [071702-1/10] Mots-clés : Heat  transfer  Turbulence  promoter  Triangular  channel  High  rotation  number Index. décimale : 536 Chaleur. Thermodynamique Résumé : Heat transfer and pressure drop have been experimentally investigated in an equilateral triangular channel (Dh=1.83 cm), which can be used to simulate the internal cooling passage near the leading edge of a gas turbine blade. Three different rib configurations (45 deg, inverted 45 deg, and 90 deg) were tested at four different Reynolds numbers (10,000–40,000), each with five different rotational speeds (0–400 rpm). The rib pitch-to-height (P/e) ratio is 8 and the height-to-hydraulic diameter (e/Dh) ratio is 0.087 for every rib configuration. The rotation number and buoyancy parameter achieved in this study were 0–0.58 and 0–2.3, respectively. Both the rotation number and buoyancy parameter have been correlated with predict the rotational heat transfer in the ribbed equilateral triangular channel. For the stationary condition, staggered 45 deg angled ribs show the highest heat transfer enhancement. However, staggered 45 deg angled ribs and 90 deg ribs have the higher comparable heat transfer enhancement at rotating condition near the blade leading edge region. DEWEY : 536 ISSN : 0022-1481 En ligne : http://asmedl.aip.org/vsearch/servlet/VerityServlet?KEY=JHTRAO&ONLINE=YES&smode= [...]